There's a particular kind of frustration that hits when you turn on your AC on the first genuinely hot day of the year, and nothing really happens. The unit is running, the fan is blowing, but the air coming out feels like it forgot its job. If your air conditioner is running but not cooling your home properly, you're in good company. It's one of the most common calls we get from homeowners across Mississauga and the GTA every spring. And honestly? Nine times out of ten, the cause is something surprisingly straightforward. Let's walk through what's likely going on.